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PROTEINS AND PROTEIN METABOLISM- Part 1
See all quizzes of PROTEINS AND PROTEIN METABOLISM- Part 1 here:
1. All proteins contain the
(A) Same 20 amino acids
(B) Different amino acids
(C) 300 Amino acids occurring in nature
(D) Only a few amino acids
2. Proteins contain
(A) Only L- α – amino acids
(B) Only D-amino acids
(C) DL-Amino acids
(D) Both (A) and (B)
3. The optically inactive amino acid is
(A) Glycine (B) Serine
(C) Threonine (D) Valine
4. At neutral pH, a mixture of amino acids
in solution would be predominantly:
(A) Dipolar ions
(B) Nonpolar molecules
(C) Positive and monovalent
(D) Hydrophobic
5. The true statement about solutions of
amino acids at physiological pH is
(A) All amino acids contain both positive and
negative charges
(B) All amino acids contain positively charged
side chains
(C) Some amino acids contain only positive
charge
CHAPTER 3
PROTEINS AND PROTEIN METABOLISM
(D) All amino acids contain negatively charged
side chains
6. pH (isoelectric pH) of alanine is
(A) 6.02 (B) 6.6
(C) 6.8 (D) 7.2
7. Since the pK values for aspartic acid are
2.0, 3.9 and 10.0, it follows that the
isoelectric (pH) is
(A) 3.0 (B) 3.9
(C) 5.9 (D) 6.0
8. Sulphur containing amino acid is
(A) Methionine (B) Leucine
(C) Valine (D) Asparagine
9. An example of sulphur containing amino
acid is
(A) 2-Amino-3-mercaptopropanoic acid
(B) 2-Amino-3-methylbutanoic acid
(C) 2-Amino-3-hydroxypropanoic acid
(D) Amino acetic acid
10. All the following are sulphur containing
amino acids found in proteins except
(A) Cysteine (B) Cystine
(C) Methionine (D) Threonine
11. An aromatic amino acid is
(A) Lysine (B) Tyrosine
(C) Taurine (D) Arginine
28 MCQs IN BIOCHEMISTRY
12. The functions of plasma albumin are
(A) Osmosis (B) Transport
(C) Immunity (D) both (A )and (B)
13. Amino acid with side chain containing
basic groups is
(A) 2-Amino 5-guanidovaleric acid
(B) 2-Pyrrolidine carboxylic acid
(C) 2-Amino 3-mercaptopropanoic acid
(D) 2-Amino propanoic acid
14. An example of α-amino acid not present
in proteins but essential in mammalian
metabolism is
(A) 3-Amino 3-hydroxypropanoic acid
(B) 2-Amino 3-hydroxybutanoic acid
(C) 2-Amino 4-mercaptobutanoic acid
(D) 2-Amino 3-mercaptopropanoic acid
15. An essential amino acid in man is
(A) Aspartate (B) Tyrosine
(C) Methionine (D) Serine
16. Non essential amino acids
(A) Are not components of tissue proteins
(B) May be synthesized in the body from essential
amino acids
(C) Have no role in the metabolism
(D) May be synthesized in the body in diseased
states
17. Which one of the following is semiessential
amino acid for humans?
(A) Valine (B) Arginine
(C) Lysine (D) Tyrosine
18. An example of polar amino acid is
(A) Alanine (B) Leucine
(C) Arginine (D) Valine
19. The amino acid with a nonpolar side chain
is
(A) Serine (B) Valine
(C) Asparagine (D) Threonine
20. A ketogenic amino acid is
(A) Valine (B) Cysteine
(C) Leucine (D) Threonine
21. An amino acid that does not form an α-
helix is
(A) Valine (B) Proline
(C) Tyrosine (D) Tryptophan
22. An amino acid not found in proteins is
(A) β-Alanine (B) Proline
(C) Lysine (D) Histidine
23. In mammalian tissues serine can be a
biosynthetic precursor of
(A) Methionine (B) Glycine
(C) Tryptophan (D) Phenylalanine
24. A vasodilating compound is produced by
the decarboxylation of the amino acid:
(A) Arginine (B) Aspartic acid
(C) Glutamine (D) Histidine
25. Biuret reaction is specific for
(A) –CONH-linkages (B) –CSNH2 group
(C) –(NH)NH2 group (D) All of these
26. Sakaguchi’s reaction is specific for
(A) Tyrosine (B) Proline
(C) Arginine (D) Cysteine
27. Million-Nasse’s reaction is specific for the
amino acid:
(A) Tryptophan (B) Tyrosine
(C) Phenylalanine (D) Arginine
28. Ninhydrin with evolution of CO2 forms a
blue complex with
(A) Peptide bond (B) α -Amino acids
(C) Serotonin (D) Histamine
29. The most of the ultraviolet absorption of
proteins above 240 nm is due to their
content of
(A) Tryptophan (B) Aspartate
(C) Glutamate (D) Alanine
30. Which of the following is a dipeptide?
(A) Anserine (B) Glutathione
(C) Glucagon (D) β -Lipoprotein
